Magnetic field induced spin-wave energy focusing

TL;DR

This paper demonstrates a method to focus and control spin wave energy in ferromagnets using local magnetic field modifications, enabling precise energy delivery for spintronic applications.

Contribution

It introduces a novel approach for energy focusing of spin waves through local magnetic field manipulation, enhancing control in spintronic devices.

Findings

Energy accumulation far from the source is achievable.

Location and amount of energy can be precisely controlled.

Method is robust and adaptable for device integration.

Abstract

Spin waves can transport both energy and angular momentum over long distances as they propagate. However, due to damping, their amplitude decreases exponentially as they move away from the source, leaving little capability for manipulating how much energy and angular momentum is to be delivered where. Here we show that a suitable local reduction of the effective field can lead to a large accumulation of spin wave energy far from the source. Moreover, both the location and the amount of energy to be delivered can be controlled accurately with geometry and externalm magnetic fields. Thus, we put forward a general, robust and flexible approach to convey both heat and spin in ferromagnets, which can be directly used in spintronic devices.